1. Technical Field
The present invention relates to an optical unit having improved optical characteristics, and more particularly, to a method of manufacturing the optical unit, a backlight assembly having the optical unit and a display device having the optical unit.
2. Discussion of the Related Art
A liquid crystal display (LCD) is one of the most widely used flat panel displays. For example, an LCD is commonly found in a variety of electronic devices such as flat screen televisions, laptop computers, cell phones and digital cameras.
An LCD device displays an image using electrical and optical characteristics of liquid crystals. For example, in the LCD device, an arrangement of the liquid crystals varies in response to an electric field applied thereto, thus a light transmittance of a liquid crystal layer including the liquid crystals is changed. Since the liquid crystals are non-emissive type display elements, the LCD device uses a backlight assembly.
The backlight assembly is classified as a direct illumination type or an edge illumination type. The direct illumination type backlight assembly includes a plurality of light sources on a lower portion thereof. The edge illumination type backlight assembly includes a light guiding plate and a light source located on a side of the light guiding plate.
The backlight assembly includes a plurality of optical parts to improve optical characteristics such as luminance uniformity, luminance, etc., of light generated from the light source. The optical parts may include a number of optical sheets such as a diffusion plate, a diffusion sheet, a prism sheet, a brightness enhancement sheet, etc. When the number of the optical sheets is increased, a thickness of the backlight assembly is increased.
A conventional brightness enhancement sheet such as a dual brightness enhancement film (DBEF) is generally used in the backlight assembly. However, the DBEF is expensive, thereby increasing a manufacturing cost of the backlight assembly. Therefore, a need exists for an apparatus that is capable of reducing the thickness of the backlight assembly and increasing the display brightness of the LCD device in a cost effective manner.